Dev v2.19.3

[TomerStarkware]

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PR Summary

Medium Risk
The entry-point ABI validation change can reject contracts that previously compiled; version bumps affect all published crates and fixture hashes.

Overview
Releases 2.19.3 by bumping the workspace, corelib, lockfiles, and internal cairo-lang-* path dependency pins from 2.19.2, and updating scripts/bump_version.sh’s CURRENT_VERSION.

Starknet contract compilation: current_sierra_version_id() patch is raised to 1.9.2. Entry-point return validation in casm_contract_class.rs now requires the error variant’s panic field to be an empty struct (so the error layout matches an Array<felt252> on the ABI), via new is_empty_struct and a check in is_valid_entry_point_return_type.

Starknet test contract JSON fixtures are refreshed for compiler_version 2.19.3 and the updated Sierra program version words in sierra_program headers.

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[reviewable-StarkWare]

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